The present invention relates to a sheet feeding device for feeding a printing sheet on which a printing operation is executed, which is employable in a printer and the like and arranged to includes two pairs of rollers respectively provided upstream and downstream of a printing unit including a platen and a printing head, for feeding the printing sheet toward the printing unit and discharging the printing sheet on which a printing operation has been executed, more particularly to a sheet feeding device capable of securely nipping the printing sheet at the discharge side even if the printing sheet is skewed or bent.
Conventionally, printers which are provided with pairs of feed rollers on a feed side and a discharge side of a printing unit for nearly straightly feeding various sheets such as cards and lables have been known.
In this structure, as illustrated in FIG. 1A, a sheet sent toward a pair of sheet feed rollers 4 on the feed side is precisely guided between the rollers 4 by providing upper and lower guide plates 61 and 62. Between the feed rollers 4 and a pair of sheet discharge rollers 5 on the feed side and the discharge side, the sheet on only the platen 1 side is guided with the guide plate 63. However, on a print head 2 side between the feed rollers 4 and the discharge rollers 5, a space for shifting a multiple color ink ribbon 64, as indicated by an arrow, in a width direction is required. Thus, a guide plate cannot be provided near the print head 2.
In the above structure, when the sheet is sent from the feed rollers 4 to the discharge rollers 5, if the leading edge of the sheet is bent or skewed to the print head 2, as illustrated with one dot line 65 in FIG. 1a, it is not nipped between the discharge rollers 5 and thereby a sheet jam may occur.